Pinking shears



July 3, 1934. F WYNER ET AL 1,965,443

PINKING SHEARS Filed March 17, 1932 INVENTOR 1 EL/X I ITJ/VEE.

ZZM/Aeo 15' CHULZ.

BY HIS W Patented July 3, 1934 UNITED STATES PATENT OFFICE PINKINGSHEARS Felix Wyner, New York, and Edward Schulz, Flushing, N. Y.,assignors to Samuel Briskman,

New York, N. Y.

This invention relates to new and useful improvements in hand cuttingtools, and more particularly it pertains to hand shears of the typedisclosed in our pending application, filed February 5, 1931, Serial No.513,734, of which this application is a continuation in part.

It is the object of the present invention to provide a pair of handshears which will cut zig-zag edges on pieces of material and which areparticularly adapted to form sample swatches.

We are aware that devices purporting to perform the aforementionedfunction have heretofore been devised, but to the best of our knowledge,and by actual experiment with such devices with which we are familiar,this result has not been satisfactorily obtainable by any device of theshears or scissors type prior to the device herein illustrated.

While the invention has been herein illus- 2o trated'as constructed toprovide a zig-zag edge, it is to be understood that the invention is notto be limited to this specific type of edge and that other edges ofirregular form may be cut by tools constructed in accordance with thepresent invention.

With the above and other objects in view, reference is had to theaccompanying drawing, wherein:

Figure 1 is a view in sidev elevation of a pair of shears constructed inaccordance with the present invention, the shears being shown in closedposition,

Figure 2 is a plan view of the shears taken at right angles to Figure 1,

Figure 3 is a detail sectional view taken on the line 3-3 of Figure 1,

Figure 4 is a plan view of one of a pair of cutting elements constructedin accordance with the present invention and illustrating said elementin one of the early. stages of its development,

Figure 5 is a transverse sectional view taken on the line 5-5 of Figure4 and on a slightly enlarged scale, and;

Figure 6 is a transverse sectional view on an enlarged scale of one ofthe cutting elements after the same has been completely formed.

Referring again to the drawing, and specifically to Figures 1 to 3inclusive thereof, a shears constructed in accordance with the presentinvention comprises two jaw members 15 each of which is provided with ahandle or gripping portion 16. These jaw members 15 are pivotallyconnected together as at 1'1 to operate about an axis 1'1 in the mannerof an ordinary pair of cutting shears. If desired, a spring or similarresilient member 18 may be employed to insure proper co-action of thecutting edge which will be hereinafter described.

As best illustrated in Figures 3 and 4, each of the jaw members 15carries a cutting element designated 19, and these cutting elements 19have coacting cutting edges which will be specifically hereinafterdescribed. The cutting elements 19 are preferably removably secured totheir respective jaw members 15, and for this purpose screws or the like20 passing through the cutting elements 19 and having threadedengagement with recesses in the jaws 15 may be employed.

It will be noted that the cutting elements 19 are of relatively thin andnarrow elongated formation, and when secured to their respective jawmembers, extend longitudinally thereof in parallelism with thelongitudinal axis of the jaw member, and slightly overhang the same asdesignated at 21 in Figure 3.

In the present embodiment of the invention, these cutting elements 19are formed with a cutting edge which will produce the zig-zag cut, andin constructing a pair of cutting elements 19 to produce this result,the said cutting elements are each provided along one edge with azig-zag or serrated cutting edge such as designated at 23 in Figure 4.The serrations are formed preferably by a milling operation as describedin a copending application, filed March 17, 1932, Serial Number 599,452,and the serrations are each undercut. These zig-zag edges of the twocutting elements 19 are complementary and when placed together willengage each other substantially throughout the entire serrated edge ofthe cutting elements.

After the cutting elements 19 have thus been made, short arcuate faces20 are formed on the sides of the teeth. This may be done by lappingoperation only or first by a shearing operation and then by a lappingoperation and if the latter is used a pivoted or rotary lapping tool isemployed. In either event, at the end of the lapping operation the areshaped faces of one cutting element will be exactly complementary to thecorresponding arc shaped faces of the other element and as the bladesare operated in the lapping machine, the corresponding complementary arcshaped faces will have a wiping closely engaging contact.

If the faces are first sheared and then lapped both the shearing andlapping operations will take place about the same center which will havea definite relation to, but will not coincide exactly with the operatingcenter when the two cutting elements are mounted on the jaws of theshears, as will be pointed out below.

During the lapping operation or during both the shearing and lappingoperations, the two cutting elements are not radially disposed withrespect to the center about which they are lapped or both sheared andlapped but are off-set a suitable distance therefrom. After the areshaped faces have thus been formed on a portion of the relatively narrowserrated and undercut edges of the cutting elements, these edges will beleft with receding or undercut portions which recede from the bottom ofthe are shaped faces 20. These receding or undercut portions permit offree clearance of the cutting edges as the short or narrow are shapedfaces pass out of engagement with one another during a cuttingoperation, this being very important to insure a clear cutting orshearing actionof the tool.

The cutting elements 19 are preferably so mounted upon the jaws of ashears that when they are secured in. place the center of operation ofthe jaws designated 17 does not coincide with the center about which thearc shaped faces were lapped or sheared and lapped but on the other handthe faces or seats 40 of the jaws on which the cutting elements rest areso located that the cutting elements 19- will be off-set a slightlygreater amount from the operating center 17' than they were from thelapping or shearing and lapping center. This causes the are shaped faces20 of one cutting element to become slightly eccentric with respect tothe co-operating or corresponding are shaped faces of the other cuttingelement. That is to say, though the corresponding are shaped faces ofthe two elements were concentric at the end of the lapping operation, inthe finished shears they are slightly eccentric. When the shearingelements are tightened on the jaws they are thus so positioned thatsubstantially only the edges of the arc shaped faces of the two shearingelements contact with each other during the cutting operation, therebycausing the cutting edges to clear each other even more rapidly thanthey would have'cleared by reason of the undercutting extending from thebottom of the arc shaped faces as already described. This slighteccentricity of the are shaped faces due to the small off-setting whenthe shearing elements are mounted in final position on the jaws,therefore enhances the good clean cutting action obtained by virtue ofthe undercutting.

The extent ofthis additional off-setting is not in all cases uniform butin any event it is slight compared with the offsetting which exists whenthe cutting elements are being lapped or both sheared and lapped. Inshears which we have produced exactly the same as herein illustrated theoff-set which the shearing elements had during the lapping or bothshearing and lapping operations was about one quarter A) of one inchfrom the center of rotation during these operations whereas in thefinished shears each shearing element is off-set and additional amountequal to approximately onesixty fourth (1 /64) of one inch. It will beunderstood that the two shearing elements will be each off-set the sameamount but in opposite directions from the operating center 1'7, thetotal amount of off-set of each jaw being indicated by the line AA inFigure 1.

From the foregoing, it is apparent that the present invention provides anew and novel ,pivotally attached together, a shearing blade carpinkingshears which is highly effective in its construction and operation, andin which as has been demonstrated in actual hand shears constmcted inaccordance with this invention, it is highly practical and willeffectively cut the thinnest of materials, an operation of which suclrdevices of the prior art with which we are familiar are incapable ofperforming.

While the invention has been herein illustrated in a preferred form, itis to be understood that the invention is not to be limited to thespecific construction or details herein illustrated and that it may bepracticed in other forms without departing from the spirit thereof.

Having thus described the invention, what is claimed as new and what isdesired to secure by Letters-Patent of the United States, is:

1. Pinking shears with pivoted blades having serrations with opposedcomplementary curved faces eccentrically disposed with respect to thepivotal center of the shears so as to provide contacting shearing edges.7

2. Pinking shears having pivoted blades with serrated cutting portions,the serrations of both blades having opposed arc-shaped surfaces, thesurfaces of each blade having a common center displaced with referenceto the center of the surfaces of the other blade.

3. Pinking shears with pivoted blades having serrated cutting portionswith opposed arcshaped faces, the center of curvature of the faces of ablade being non-coincident with the pivotal center of the'shears.

4. Pinking shears comprising two pivoted blades having serrated cuttingportions, the ser- 110 rations of each blade arc shaped faces with acenter of curvature displaced with reference to the pivotal center ofthe shears. v

5. Pinking shears comprising two pivoted blades having serrated cuttingportions with are 115 shaped complementarysurfaces, the center ofcurvature of the arc-shaped surfaces of the two blades being offset onopposite sides of the pivotal center of the shears.

6. Pinking shears comprising a pair of pivoted 12 jaws each having acutting portion, a row of serrations located to one side of a lineextending radially from the pivotal axis of the jaws lengthwise of thejaws.

7. Pinking shears comprising a pair of pivoted jaws having shearingportions consisting of serrations which project inwardly from theadjacent faces of the jaws, the serrations of each jaw being on one sideof a radial line extending from the pivotal center centrally of thejaws.

8. A shearing tool comprising a pair of jaws pivotally attachedtogether, and a shearing blade carried by each of said jaws, saidshearing blades comprising relatively thin and narrow members havingcutting edges, and cooperating undercut portions receding from a pointremote from said cutting edges as and for the purpose described.

9. A pinking shears comprising a pair of jaws ried by each of said jaws,said shearing blades each comprising a relatively thin and narrowmember, a serrated cutting edge on each of said shearing blades, and anundercut face receding from a point remote from each serrated cuttingedge.

10. A pinking shears comprising a pair of jaws pivotallv attachedtogether, and a shearing edge for each of said jaws, each of saidshearing edges comprising a serrated cutting edge, a relatively shortface extending from said cutting edges, and an undercut face recedingfrom each of said first mentioned faces.

11. A pinking shears comprising a pair of pivotally attached Jaws, and acutting blade extending longitudinally of each of said jaws, saidcutting blades having interengaging serrated side edges and curved facesin a vertical plane of the serrations, and being relatively thin wherebythey pass clear of each other after the completion of a cuttingoperation.

12. A pinking shears comprising a pair of pivoted blades havinginterengaging serrated side edges having curved faces in a verticalplane of the serrations said blades being relatively thin or narrowwhereby they pass clear 'of each other after the completion of a cuttingoperation.

13. A pair of scissors or shears comprising pivoted blades, lipsprojecting from said blades into cooperable relationship, notchedcutting edges on corresponding portions of each of said lips, saidnotches being disposed in predetermined relationship to each other.

14. Pinking shears comprising a pair of pivotally connected blades, arelatively thin and narrow flange extending along the inner edge of eachof said blades, each of said flanges projecting at substantially rightangles from its respec-- 'tive blade, and a plurality of serrationsformed in the flange of each of said Jaws and extending entirely throughthe flange.

FELIX WYNER. EDWARD SCHULZ.

